Yes, I’m not against it, I feel it can be an effective stepping stone towards an ideal solution. It should not be overdone, of course. So more a mitigation feature than a resolution.
I don’t have anything in mind right now. But also, for that to be effective, we would need the change in background proposed here: XWiki onboarding tour so that the context for the user is maintained.
All in all, for me, the Tour App and Onboarding App are complementary to each other and not mutually exclusive.
We can also imagine scenarios of the tour app being used to point to small quality of life improvements in the UI. Small texts like “Your notifications are now here", or “You can start following this page here". These would be useful for users coming from an older version, but not necessarily new ones (is there a way to only show onboarding steps for these users?)